Space telegraphy.



J. s. STONE.

SPACE TELEGRAPHY. APPLICATION FILED HAILIE. 1908.

986,65 1 Patented Mar. 14, 1911,

3 BHEETS-BHEBT 1.

QELW

- MQ M J. S. STONE.

SPACE TELEGRAPHY.

APPLICATION FILED 11442.12, 190a.

Patented Mar. 14, 1911.

3 8HEETSSHEET 3.

WIT IEEEEE.

UNITED STATES PATENT onrrcn JOHN STONE STONE, 013 BOSTON, MASSACHI-USECII'II'S.

SPACE TELEGBAPHY.

Specification of Letters Patent.

Patented Mar. 14, 1911'.

Original application filed February 27, 1906, Serial No. 303,213. Divided and this application filed March Serial No. 420,590.

vTo all whom it may concern:

Be it known that I, JOHN STONE STONE, a citlzen of the United States, and a resident- I of Boston, in the county of Suffolk and State of' Massachusetts, have invented a new and useful Improvement in Space Telegraphy, of which the following is a specification.

My invention relates to space telegraphy, and its objects are to provide certain novel circuit arrangements for space telegraph systems and to provide certain improved details of construction which may be employed invention is'.not limited to the particularembodiments thereof which are illustrated in said drawings, lnasmuch-as my inventlon may be subjected to a wide range of variation without departing from the principle thereof.

In the drawings, Figure lfdiagram-mati- .c'ally represents a combined transmitting and receiving space telegraph system; 'Fig. 2-is a sectional view of oneform of coil that may-be employed; Fig. 3 is a front elevation of one form of receiving set embodying my invention; Fig. 3 is a fragmentary view of a modification of the' receiving. set shown in Fig. 3 Fig. 4 is a sectional view taken at right angles to the View shown in Fig. 3 with certain elements illustrated in Fig. 3-

'omitt'ed, and showing, the hinged ,cover of the receiving set casing which has been omitted from Fig. 3'; Fig. 5 is a plan view of the 'transformer Iifz and the means-whereby the position oftlie same with respect toits pri- Ii mary may be regulated: Fig. 6.is an end view ofthereceiving, set shown in Fig. 3

' illustrating-the hinged cover 15 ofthe receiver'casing. which has-been omitted from- Fig. 3; Fig, 7 is'a-plan-view of the-movable condenser plates; Fig. '8 is a'plan view of-the' Fig. 9 is a sidestationary condenser platesi view of said movable plat s, said plates beingshown in front View in Fig. 3 .and Fig. 10 is a front view of that portion of the hinged cover of the receiver set casmgwhich closes that compartment thereof containing the transformer M.

In the figures, A is an alternating-current generator; V is an elevated conductor; E E are earth-connections; M'M M M are I transformers, of whichthe primary and secondary windings respectively are I I etc.,

and I. I etc; C C C, etc, are condensers; P is an oscillation responsive device herein shown as a VVollaston anode W in an electrolyte contained in a cup P; T is a telephone receiver or other suitable signal-indicating'device; B is a battery; R is a resist ance; S s s are spark-gaps; L is an inductance; is a key and'F F are fuses.

In Fig. I the circuit S C I; is a sonorous or persistently oscillating circuit inductively associated with the elevated conductor sys tem V I E by means of the transformer M whose windings I I preferably are so spatially related as to render the period of said sonorous circuit practically inde endent of the electromagnetic constants o said elevated conductor system, as more fully expla-ined in the aforesaid-patents. The circuit containing the alternator A and the primary I, of the transformer M is the primary power circuit, the energy .of which is delivered the desired tension to said sonorous circuit by means of said transformer.

For the purpose ofprotecting the arm-ature windings of the alternator A, I connect the branch circuit a 7) across the terminals of. said alternator andconnect one armature of-th'e condenser C"-included in said circuit to the frame H of the alternator, so that any, electrical oscillations-which -may be created in the primary. power circuit by the reaction of the sonorous circuit thereon, will be prevented from creating a difference of potential between said armature windings and the metallic parts ofthealternator which lie adja'cent to said windings "In order to rotect the condenser C" from the effects 0 excessivei.oscillatingpotentialswhich may be developed between the points a and 7), Iconnectaspark-gap 8 across the terminals of said condenser." In order toprotect the alternator from. excessive currents which may be developed in the primary power circuit in case of condenser breakdown or. are at:- the spark-gap 8- caused-by the reactlon of the sonorouscircuit thereon or from any."

other cause I may connect a fuse F on either side of the condenser C in the branch a Z).

A branch 0 d is connected across the terminals of the primary I of the transformer M and is connected to earth at E. A spark gap 8 is connected across the armatures of the condenser C which is included in said branch c d. By means of said branch 0 d and its connection to earth d E, the primary I of the transformer M and the armature of the alternator A are protected from excessive potentials or currents de-, veloped in the primary power circuit by the reaction thereon of the sonorous circuit S C 1,. For the purpose of further protecting said primary power circuit as above set forth from excessive currents a fuse F may be connected on one side of the condenser C, but obviously is not needed on the earthed side thereof. Both condensers C and C should be so proportioned that each of the branches a and c d should have for the frequency of the power current an imped ance high as compared to its impedance for the frequencies of the oscillations developed in the sonorous or oscillating circuit.

The condenser C shown in the present instance as connected across the terminals of the primary of the transformer M, has its capacity so related to the inductance of the pr1mary power circuit as to reduce the impedance of the primary power circuit for currents of the frequency developed therein by the alternator A and thereby increase the power factor of said circuit. Obviously the condenser G may be arranged in other ways for eifectingthis result. It will of course be understood that,.in general, the capacity of the condenser C is larger than the capacity of either of the condensers C C",

The elevated conductor is connected to the spring contact 25 at the point 0 and the contact member which cooperates with said contact t is connected to earth at E. gBetween the points 0 and o'the receiving sys-' tem is connected and it will be apparent that upon the depression of the key K the projection tpresses the spring t into con tact with its cooperating member and closes the contact k thereby short-circuiting the receiving system between the points 0 0 and thereby connecting the receiving systein to the elevated transmitting conductor s 'stem V I 0, t 0 E at a point having practically zero potential to earth. It will be apparent also that the potential difference developed between the points 0 0" during transmission, even" when currents of very large amplitude are developed in said elevated conductor system, will be negligibly small and will not develop in the receiving system currents of sufficient amplitude to injure the delicate parts thereof such as the coil L or the coils of the transformers M M".' Simultaneously with, or before or contained in the cell P. It is immaterial,

whether the anode be raised out of contact with said electrolyte before or after the closure of the contact all that is necessary being that both these operations occur prior to the closure of the contact is.

I do not wish to limit myself to the particular means shown in Fig. 1 and described above for rendering the receiver inoperative, inasmuch as various other means may be em ployedfor this'purpose.

The elevated receiving conductor system consists of the elevated conductor per 86 V, the secondary I the conductor connecting the latter to the point 0, the inductance L, the parallel branch circuit C, I and the conductor connecting the latter to earth'at E. Theelectromagnetic constants of said' parallel branch circuit are so proportioned that for a persistent train of wavesof the frequency to which the resonant receiving circuit 1 0 is attuned said parallel branch circuit will balance by its reactance the reactance of the rest of the elevated receiving conductor system, in which system it will be noted, the secondary 1 operates merely as an inductance. The resonant weeding-out circuit C" I I may, if

of thecondenser C which is one of the tunin elements of saidresonant circuit, and

there ore across the terminals of this condenser I connect the electrolytic receiver 1 in lieu of connecting said receiver in series with said resonant circuit. The apparent resistance of the electrolytic receiver P is large and if such receiver is connected in series with the resonant receivingx circuit-the selectivity of said circuit isconsiderably reduced. Furthermore the electrolytic capacity of said receiver is not quite constant so that by connecting an electrolytic receiver across a point of maximum potential development of said circuitand in shunt to a condenser of relatively large capacity, the receiver ex erts a much less pronounced effect upon the selectivity of said circuit than when it isserially connected therewith. The signalindicating device T and the variable resistance R, which resistance with the battery B and contact 70 constitutes a potentiometer, may as shown be connected 1n series with].

the receiver P because the large distributedcapacity inherent in these devices offers but little opposition to the flow of high frequency electrical currents therethrough. If desired, a condenser C may be connected as shown across the terminals 29, g of the device T and resistance R for the purpose of increasing the capacity of the receiver'circuit and reducing the opposition of said circuit to the passage of high frequency currents therethrough.

" It is often desirable, and for commercial operation .it is necessary, that a receiving operator should be able to break the transmission from a distant station when he fails to understand a message or a portion thereof, and such operation of breaking is accomplished by the apparatus shown in Fig.

l by the simple expedient of depressing the key K. By the depression of the key IQ the receiver is rendered inoperative, the receiving system vis short-circuited by the closure of the contact 70. and the elevated transmitting conductor is connected directly to earth, and then by a further movement of the key K the cuit is closed at la thereby effecting the radiation of electromagnetic waves from the elevated conductor system. These waves are absorbed by the elevated receiving conductor system at the station from which signals are being transmitted to the receiving operator who is breaking, and when the key at said transmitting station is in normal posi-, tion the break signal may be read by the transmitting operator at said station be-. tween his own signal elements. For this purpose the operators retain the telephone T, which preferably is a head telephone, in position while sending and it will be obvi ous that the connection of the receiving sys-. tem to the elevated conductor transmitting system at a point of zero potential during transmission will permit an operator so to retain the telephone T in position with safety. It is also to be noted that the tele primary power cirphone Tbeing in a tertiary circuit is not 'conductively connected. to the transmitting system at'any time. It will be noted that the means operated by the sending device K v for short-circuiting the receiving system between the points 0 0 are not connected either electrically or mechanically with said sending device.

In my United States Patents Nos. 714,756,

dated Dec. 2,. 1902, and 767,977, dated Aug. 16, 1904,. I have discussed at length the advantages resulting from tuning coils haying their kinetic energy large compared to their potential energy when the circuit in which such coil is included is supporting a current of the frequency to which said circuit is attuned, or hafiring the'length'of conductor constituting the. coils a fraction of half a wave-length of'the potential orthan a coil formed of a. single wire.

is, lined with a conductor.

current along the coi lin other words having such length of conductor short compared to the halfwave-length of the waves cor,-

responding to the frequency to which the circuit including the coil is attuned.

In Fig. 2 I have shown 1m section one form of coil possessing the foregoing characteristics. This coil is'fortmed of fine stranded wires which may be "twisted together so as to form a cable 14 and said cable may be wound upon the spool 13. It is capable of demonstration that such a coil possesses, for a given inductance a much smaller distributed capacity and resistance In other words, a coil constructed as above described possesses a .maximum electromagnetic time constant and a minimum electrostatic time constant so that, other things being equal, the persistence and selectance of a circuit including such coils are greatly improved.

In Fig. 3 is shown one of the numerous concrete embodiments of the circuit arrangements described in my prior patents, especially in vUnited States Patent No. 7 67,994.

In Fig.3 the receiving set is identical as to. its 'circuital arrangements with the receiving system shown inFig- 1. The coil I the spring t, its cooperating contact, the earth connection E and a portion ofthe key K are all shown diagrammatically in Fig. 3, as well as the receiver P, telephone T and potentiometer BR. The rest of the apparatus .is shown in front elevation. This apparatus consists of a casing 15 divided into two compartments each'lined with tin 17 18,- or othersuitable conductor to eliminate as far as possible the effects of stray magnetic field s,;and more particularly to prevent mu; tual inductance between coils I, and 1 As indicated in Fig. 4, and as shown in Fig. 6, the casing 15 is provided'with a hinged cover 15 which also may be, and preferably In the righthand compartment of the casing 15 the rod 1, mounted on the side of the casing by suit able supports 1', is provided at its outer end with a boss 4 provided with a slot 5 adapted. to receive a projection 5 carried by the-knurled head 6, so that when the cover 15, which is connected with thecasing 15 byv the hinges 20, is closed, .the rod 1 may be rotated by means Of'said knurled head. Attached to 'theinner end of the rod' 1 is the member 2 extending at right angles to the rod 1, anddepending from said mem-' her 2 at right angles thereto is the rod'3 which carries the secondary winding 1, of

the transformer M at its lower end. The primary coil I, is secured in anysuitable manner to "the base of the compartment so thatit will be directly under the secondary coil when the needle 21'which is secured to the head 6 points downward as shown in ductance between the primary and second-- ary winding of the transformer M will be a ,minimum as indicated by the word weak printed on the cover and when said secondary has the position shown in Figs. 3 and 6, said mutual inductance is a maximum as indicated by the word strong 1 printed on said cover.

By virtue of the construction described above, it is possible to regulate the coefficient of coupling without opening the transformer compartment. Leads from the pri mary I," pass through the holes a b in the back of the casing and one of them connects with the coil L while the other connects with one armature of the condenser C passing through the hole a; in the back of the condenser casing. That lead from the primary 1, which connects with the coil L passes into the. condenser casing through the hole 0 in the back thereof and connects with the other armature of the condenser C thereby closing the'parallel branch circuit C 1 shown in diagram in Fig. 1. One terminal of the secondaryL" passes through the partition separating the two compartments of the receiving set casing and connects with the primary 1 of the transformer M while the other terminal of said secondary passes through the hole 6 in the back of the casing, enters the condenser compartment by the hole- 9 and connects with one armature of the condenser G The lead from the otherarmature of said condenser passes out of the condenser casing by the hole it,- enters the receiving set casing through the hole f and connects with the other terminal of the primary 1 thereby closing the resonant weeding-out circuit I, C, 1 shown in diagram in Fig. 1. The secondary 1 of the'transformer M connects with the condenser 0 by leads which pass out of the receiving set casing by the holes a j, and which pass into the condenser casing by the holes k Z, thereby closing the resonant receiving circuit. Across the terminals of the condenser 0 the' circuit of. the receiver P is connected, 0 and the condenser 'C., if employed, is connect'e d across that part of the receiver circuit' containing the telephone T and the variable resistance R by leads which pass from the points p g into the condenser casing through the holes m 'n. The rod 19 which .much looser coupling between the resonant weeding-out circuit, if such circuit be employed, and the elevated conductor system or between the resonant receiving circuit, if the resonant weeding-out circuit be not employed, and the elevated conductor system, than could be produced conveniently by the means shown in Fig.3, and such extremely loose coupling may be efifected by the construction shown in Fig. 3. In Fig. 3 the rod 22 is attached to the secondary I, at a point on one side of the center thereof and is adapted to move vertically in the slots 25 with which the opposite sides of the casing are provided. To reduce the coefiicient of coupling, the rod 22 is raised vertically and rotated so that the secondary 1., assumes a position directly in line with the axis of the primary 1,", in which case there should theoretically be absolutely zero mutual inductance between the windings, but in which there is suflicient mutual inductance to ermit an extremely persistent train of oscillations to energize the circuit in which the secondary I is included.

The construction of the condensers which I prefer to employ is shown in Figs. 3, 6, 7, 8 and 9. Each condenser consists of a series of stationary supporting plates 9 of any suitable'insulating or conducting material, each carrying on both its sides a sheet of conducting material 10' conductively con nected together by the metallic clip 7 Each condenser comprises also a series of movable supporting plates 9, each carrying on both its sides in like manner a sheet of conductive material 10- connected together by the metallic clip 7 whichis provided with a handle 8. The base 11 of the condenser casing is providedwith grooves which receive the stationary supporting plates 9 and retain them properly separated, and which receive also .movable plates and cooperating with the pointer 24 attached to the base of the condenser casing. By the use of such condensers 'I am enabled to Vary in a perfectly smooth and continuous manner the natural periods of the several circuits includmg the condensersand to quickly adjust the several circuits of the system to the frequency of the waves the energy of which is to be received.

This application is a division of my applicat-ion Serial No. 303,213, filed February 27,1906. I

I claim,-

1. In a space telegraph system, a resonant circuit attuned to thefrequency of the waves the energy of which is to be received and including a condenser, and an electrolytic receiver connected in shunt to said condenser.

2. In a space telegraph system, a resonant circuit attuned to the frequency of the waves the energy of which is tobe received, and an electrolytic receiver connected in shunt to a vatedconductor, serially connected therewith, a resonant tuning element of said resonant circuit.

3. In a space telegraph system, a coil formed of stranded wire of lengths whlch are short compared to the halfwave-length of the waves corresponding to the frequency to which the circuit including said coil is attuned.

4. In a space telegraph system, a circuit resonant to a given high frequency and in cluding a coil formed of stranded wire, said coil having the amplitude of its potential energy small compared to the amplitude of its'kinetic energy when supporting a current of said given high frequency.

5. In a space, telegragh system, an elea para lel branch circuit member may be rotated.

7. In a wireless telegraph receiving set, a compartment provided with a hinged cover, a rod in said. compartment carrying one of'the coils of a transformer and means carried by said cover and cooperating with said rod whereby said rod may be rotated to vary the spatial relation of said coils.

8. In a wireless telegraph receiving set, a

of said transformer and means whereby said compartment lined with conducting material, a transformer located in said compartment and means extending through said compartment whereby the spatial relation of the windings of said transformer may be varied without opening said compartment.

In testimony whereof, I have hereunto subscribed g JOHN STONE STONE.

Witnesses:

, CHARLES C. KURTz,

GEO. K. WOQDWORTH.

my name this 4th day of March 

